# In a mixture of ammonia and hydrogen hypochlorite, how do I determine the oxidising and reducing agent?

$$\ce{NH_3 + HOCl <=> NH_2Cl + H_2O}$$

How do I figure out what the oxidizing agent is and reducing agent? I know that the oxidizing state of $N$ in $\ce{NH_3}$ is $-3$, but I'm not sure how to proceed with the rest...

Oxidation numbers for $\ce{NH_2Cl}$:

• $\ce{N} =~ –1$
• $\ce{H} =~ +1$
• $\ce{Cl} =~ –1$.

for $\ce{HOCl}$:

• $\ce{H} =~ +1$
• $\ce{O} =~ -2$
• $\ce{Cl} =~ +1$

Is $\ce{NH_3}$ the reducing agent? (or nitrogen?) going from $-3$ to $-1$ and $\ce{HOCl}$ the oxidizing agent, ($\ce{Cl}$) going from $+1$ to $-1$?

You're on the right track with assigning oxidation numbers to each element. And you've assigned them successfully.

To successfully complete the task you need to define a few terms:

What's oxidation?

What's reduction?

What's the oxidizing agent? Try thinking of this in terms of what oxidation is, and then try figuring out what an oxidizing agent would do.

What's the reducing agent?

• And what is a Redox Reaction? – Devashish Das Aug 13 '14 at 4:09
• ^Good question to be asking oneself. – Dissenter Aug 13 '14 at 4:11
• Thank you! Oxidation would be the loss of at least one electron, and reduction is the gain of at least one. Oxidizing agent is the one that is reduced because it lets the other one get oxidized. So if Nitrogen in NH3 is going from -3 to -1, it is losing electrons (since charge is increasing) meaning it is oxidized, making it the reducing agent? – user3325170 Aug 13 '14 at 4:32